Leather-skiving machine.



t STAWENT OFFICE ALEXANDER M. ALEXANDER, 0F BEVERLY, MASSACHUSETTS, ASSIGNOR TO UNITED SHOE MACHINERY COMPANY, OF PATERSON, NEW JERSEY, A CORPORATION OF NEW JERSEY.

LEATHER-SKIVING MACHINE.

To all whom it may concern Be it known that I, ALEXANDER M. AL X- .mnnn, a citizen of the United States, resid ing at Beverly, in the county of Essex and State of Massachusetts, have invented certain new and useful Improvements in Leather-Skiving Machines; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

The present invention relates to means for preventing the accumulation of chips or skivings in or about the knife of a skiving machine, and is intended primarily for use in machines of the type disclosed in an application filed by George E. WVarren, Serial No. 481,117, dated March 3, 1909. It is to be understood, however, that while the invention is particularly adapted for use in machines of the class disclosed in said ap plication, the invention is also applicable to other forms of leather skiving machines. I

In the skiving machine above referred to, the pieces of leather to be skived are fed to a rotary cylindrical knife by means of a feed roll cooperating with a presser foot. In the operation of the machines as heretofore constructed, the chips or skivings are occasionally carried up outside of the cylindrical knife by the suction produced by the knife as it rotates at a very high rate of speed. The chips thus carried up by the knife are liable to become wedged so tightly between the knife and the frame of the machine that the knife becomes heated and its temper is drawn.

One object of the present invention is to overcome this difiiculty in a simple and emcient manner. To this end one feature of the present invention contemplates the provision of a guard which shall act to prevent the chips from being carried up by the knife and accumulating against the same. In the present embodiment of the invention the guard comprises a thin metal plate in frontand at one side of the knife and extending underneath the knife, said plate being attached to the frame of the machine.

A further object of the invention is to provide means for preventing the accumulation of chips and skivings within the cylindrical knife. To this end another feature of the invention contemplates the provision of an ejector arranged adjacent to the edge across the edge of the knife.

Specification of Letters Patent. Patented Ma 24 1914 7 Application filed October 16, 1909.

Serial No. 522,906.

of the knife so that it will act to trip or I throw the loose chips out of the knifewhenever they are brought into engagement therewith during the rapid rotation ofthe knife.

In embodying this feature in a construction provided with my preferred form of chip guard the e ector may be conveniently formed by so shaping the guard plate that its edge conforms substantially to the circle of the knife edge, and extending it slightly Theedge of the chip guard thus forms a stationary barrier extending partially around the knife edge against which the chips within the knife may strike as they are carried, around with the knife. As the chips are carried around inside of the knife and come sufficiently near the edge of the knife to encounter the edge of the ejector, it acts to trip them and cause them'to be discharged .or e ected clear of the knife. believed to be due to the fact that the chips,

This action is traveling at a high rate of speed, in encountering the ejector, are momentarily retarded at the end which comes in contact with the ejector, whereas the momentum of the opposite end of the chip is not reduced, and, as a consequence, the inertia of the chip is sufficientto cause it to jump out over the ejector.

In the preferred form of the presentin- 'vention certain novel constructions and arrangements of parts are provided which are hereinafter described and claimed. The advantages of these constructions will be apparent to those skilled in the art from the following description and an inspect-ion of the accompanying drawings.

In the drawings Figure 1 is a fragmentary side elevation of a leather skiving machine with the invention applied thereto; Fig. 2 is a fragmentary plan view of the same and Fig. 3 is a fragmentary sectional elevation of the same.

As shown in the drawings, the machine comprises a base 1, the left-hand or front end 2 of the top of which forms a work table upon which an edge gage 4 is adjustmachine.

lindrical skiving knife 22. The knife 22 is secured to a flanged end 24 of the shaft 26 journaled to rotate in a sleeve 27 mounted ina frame 28 supported by the base of the The shaft 26 is rotated by any suitable means. With this construction, as heretofore used, the chips or skivings made by the knife 22 were carried up, by the knife and wedged tightly between it and the frame 1 of the machine. This resulted in heating the knife sufliciently to draw its temper. This difficulty has been overcome by the construction illustrated in the drawings as embodying the preferred form of the invention, which comprises a chip guard 30 formed of a sheet metal plate and secured to the base of the machine by screws 31. This plate is fitted closely to the inside of the machine base and projects into close proximity with the edge of the knife 22. The plate is formed with a lateral projec tion 32 which bears against the under side of the knife 22 and extends inwardly to the back of the knife, closing the bottom of the V-shaped space formed between the side of the knife and the base of the machine, thus preventing anyrchips or skivings from being drawn up into this space by the rapidly rotating knife.

The plate 30 is cut away on the circle of the knife to form an edge 8% which extends about quarter way around the knife and projects within or across the edge of the knife a short distance. This edge thus forms a barrier against which the chips which fall within the knife near its edge strike while the knife is rotating at a high rate of speed, so that they are thereby caused to be discharged or ejected from the knife. The chips which are carried around inside of the knife, and come sufficient-1y near to its edge to encounter the ejector, are retarded at the ends which come in contact with the ejector, while the momentum of the opposite ends of the chips is undiminished. The chips are thus turned in their course, and their inertia is sufficient to cause them to be thrown out over the ejector. Thus there is no liability of the chips becoming clogged either inside or outside of the knife.

The invention having been described, what is claimed is 1. A skiving machine, having, in combination, a rotary cylindrical skiving knife, a feed roll and presser foot for feeding the material to the knife, and a guard plate extending along and covering the edge of the knife in advance of the feed devices substantially as described.

2. A skiving machine, having, in combination, a rotary cylindrical skiving knife, :1. feed roll and presser foot for feeding the material to the knife, a guard plate in front of the knife having an edge substantially concentric with, and extending across the edge of the knife, substantially as described.

3. A skiving machine, having, in combination, a rotary cylindrical skiving knife, :1. feed roll and presser foot for feeding the material to the knife, a guard plate extending along and covering the edge of the knife in advance of the feeding devices, and a lateral extension extending from the plate axially along the periphery of. the knife, substantially as described.

4:. A skiving machine, having, in combination, a rotary cylindrical skiving knife, and a stationary ejector plate having an inner edge which extends along and projects across a portion of the knife edge.

5. A skiving machine, having, in combination, a rotary cylindrical skiving knife, and a stationary plate in front of the knife having a curved inner edge which extends along and projects across'a portion of the knife edge.

6. A skiving machine, having, in combination, a rotary cylindrical skiving knife, a guard plate arranged to cover the edge of the knife along a part of its periphery and a plateextending from the end of the guard plate axially along the periphery of the knife, substantially as described.

7. A skiving machine, having, in combi nation, a rotary cylindrical skiving knife and a stationary barrier extending partially around the knife edge against which the chips within the knife may strike and over which they may pass as they are carried around by the knife.

ALEXANDER M. ALEXANDER.

lVitnesses VARREN G. OGDEN, N. D. MCPHAIL.

Copies of this patient may be obtained for ifive'cents each, by addressing the "Commissioner of Patentn.

' Washington, "D. G. 

